If anyone can tell me the name of the company / product that you use
to treat heating systems that have got a bit blocked (black gunk) I'd
I read about it here but can't remember the name.
Thankyou very much!
I've been looking for advice on this as its a sealed system but
everywhere says "get a professional". Is it really that dodgy? Are
their safety concerns (wouldn't have thought so).
I was going to tackle it like this.
Attach hose to drain cock then begin drain. Open air valves on
upstairs rads until there is no more flow.
Close upstairs air valves. Open downstairs air valves and refill from
water inlet until bottom of system is full. Close downstairs air
valves and open upstairs ones then fill up system.
Then repeat as you suggested and then fill using the F3 cleaner stuff
and follow their procedure.
Anything wrong with this approach?
From experience, this has limited effect on badly fouled systems.
Recommend Andy Hall's method:
Take off all rads and flush them through with hose until clear (invert rad
several times while flushing)
Run water off at every rad valve/bleed point until clear
If possible hook mains water up to the system and force gunge out (careful
not to over pressure system/boiler doing this).
Once you've done this and flushed the whole system several times, then run
the cleaner through.
Flush well again, add inhibitor and sit back knowing your system is tip-top.
Use only Fernox IMHO, others are cheap second place
In an earlier contribution to this discussion,
Most of the sludge will have accummulated in the radiators, and it will take
a long time to wash it out by this method.
An alternative is to remove the radiators, and take them outside and give
them a thorough wash out with a hose pipe. While each one is off, you can
wash out its pipework by opening each radiator valve in turn (with a
receptacle under it to catch the water) and have an assistant open a tap on
the filling loop to ensure you get a good flow of clean water.
As others have said, the black sludge is very indellible - so take adequate
precautions to prevent it getting spilled on carpets etc.
Ok thanks all!
I was hoping for a non time consuming solution but maybe I should get
a "pro" in. Although I'd imagine it will cost a fair bit of cash. The
main problem is not having anyone who can help me. Ok there's the
wife, but she won't carry a radiator into the garden with me!
Why not? My wife not only helped me carry the radiators out but she
cleaned up the black inky sludge that we had dripped on the way!
It's an easy job when the system is drained down and will save you £££'s
and be more effective than chemical treatments.
Another system that may work (probably not quite as well) but is less
hassle and less messy:
1) Go round and close all the inlet and outlet taps on all radiators.
Make a note of the number of turns to close the lockshield valve on each
rad so that you can restore the position later (to maintain balancing).
2) Make sure the drain point is open (and connected to a hose if
required etc). Open both taps on one radiator.
3) Then turn the system filling loop tap on. This should force mains
cold water through the one rad and out of the drain. Keep an eye on the
pressure gauge and make sure it does not rise beyond say 2.5 bar turn
down the filling loop tap a bit if it gets close.
4) Watch the drain water until it runs clear.
5) Turn off the filling loop, and close both valves on that rad, and
open the valves on the next rad.
6) go back to step 3 until all rads are done.
If you want to get flash, you could leave the filling loop on and open
the next rad before going back and closing the previous each time.
Finally restore the rad lockshield valves to their original positions.
For completeness you could then add a flushing agent like sentinel x400
and leave that in for a week before repeating the process again.
In article , John Rumm
Yep, top idea, concentrating mains flow and pressure on one rad at a
time should erode a pile of sludge in the bottom of a rad after a while
and 30mins concentrated flow per rad would be no hardship on a Sunday
diy job. To be effective I think it needs a way of isolating flow
through the boiler otherwise it'll short circuit the flow in the
radiator, my own system has one in by design but it would be worth the
o/p installing a full flow ball valve in the boiler flow for just to
make this possible.
On Tue, 29 Jan 2008 06:33:35 -0800 (PST)
Strange, I would expect it to be mostly ferric sulphide. I didn't
think that would be toxic to plants - iron salts are usually beneficial.
You live and learn. Thanks.
If it's a sealed (pressurised) system, when you open the upstairs rads
you'll get water coming out.
Also, seeing as you have a mains feed you can flush each rad in situ
with a hose on a drain valve somewhere. It's not as good as taking
them off but it'll help.
Usual disclaimers etc for primatic systems.
I'm going to go with this idea first (although I'm not too worried
about removing rads and flushing in the garden with more pressure), I
am stopping off at a diy place to pick up some system cleaner and the
corrosion protection stuff tonight as well.
There is a drain point which seems to be located up at the same height
of the boiler. The boiler is in the kitchen so the drain point is
around 5 feet off the floor. I thought it would be at floor level or
is that just open systems?
Does this sound like the drain point or could it have some other use?
(It certainly looks like the drain point :)
That could just be the drain for the boiler itself. Have a look at the
low level pipes and also at the rad valves - some have built in drain
If you need to add a low level drain point, then you can use a self
cutting washing machine tap in the first instance. The posh solution is
to plumb in a drain point that feeds through a wall to a outside gully
and is controlled from a service valve.